The worst of these is the "Google" app. For over a year, every single new version has the exact same four-entry changelog, which translating from Portuguese is something like: "enhanced search page appearance; new doodles designed for app experience; off-line voice actions, available only in the USA; web pages opened directly within the app". I have the slight suspicion that most of the almost weekly updates to the "Google" app do not have these four changes... for that app, "bugfixes and performance improvements" would actually be a better (more correct) changelog.